Improvement in machines for polishing wood



NITF'D STATES y PATENT OFFICE.

IMPROVEMENT IN MACHINES FOR POLISHING WOOD.

Specification forming part of Letters Patent N o. 54,161, dated April 24, 1866.

To all whom it may concern:

Be it known that I, FERDINAND HOFFMAN, (sometimes called FRANK HOFFMAN) of West Cambridge, in the county of Middlesex and State of Massachusetts, have invented an Improved Machine forPlaning, Scraping, Smoothing, or Polishing Wood or various other Materials 5 and I do hereby declare the. same to to be fully described in the following specification and represented in the accompanying drawings, of which- Figure l is a top view, Fig. 2 a front elevation, Fig. 3 a longitudinal section, and Fig. 4 a transverse section, of it.

- My present machine differs materially from that for which I have recently applied for Letters Patent, inasmuch as in the present machine the bed or carriage for supporting the work to be scraped or otherwise reduced is sustained in guide-grooves, and has mechanism for imparting to it reciprocating longitudinal movements under the scraper or plane-stock, which is provided with mechanism' such as will not only allow it to be pressed downward by its own weight, so as to keep the scrapers or cutters in contact with the work or article to be reduced, but will enable it to be moved laterally and gradually across the article, in order that the entire upper surface of such article may be subjected to the action of the scrapers or reducing-tools of the stock. The plane-stock, also, has lnechanism by which it may be raised oft' the work, as occasion may require.

In the drawings, A denotes the bed-frame ofthe machine, such frame being provided on its top with straight parallel guide-grooves a a, ortheir equivalents, for supporting and guiding a platform or carriage, B, for sustaining a piece of board, O, or the work to be reduced.

Two connecting-rods, D D, turning on journals b b extended from the carriage B near its front end, also turn on the pins c c of two cranked wheels, E E, which are lxed on a shaft, F, extending across the bed A, and being duly supported iu boxes rl d applied to such bed. ,The shaft F has a driving-pulley, G, xed on it, such pulley being to receive a driving-belt proceeding from a suitable motor. On revolving the shaft reciprocating rectilinear motions will be imparted to the carriages.

The plane or scraper-stock G is placed directly over the carriage, and carries two scrapers or reducing-cutters, c c, one being at each end of it, and each cutter being fastened in place in its throat by a serew,f, acting against a bearer, g.

The plane-stock is intended to be made of some heavy material, ,such as iron, and with a passage, h, extending through it transversely, and formed with vertical and parallel sides. This passage is to receive la screwnut, H, which goes through it, and has a depth less than that of the passage, and is provided with iianges i z' arranged on it and with respect to the plane-stock in manner as shown in Fig. 5, which is a horizontal. section of the said stock and the nut.

Arscrew, Ir, made on a shaft, 1, screws into and through the nut H, 'such shaft being sustained in movable boxes l l, so supported between and by vert-ical guides m m m m., arranged as represented, as to be capable of being moved upward by means of two cords, o 0, which are attached to such boxes and led around pulleyspp, and thence to a hand-bar, q. The pulleys p p, arranged as represented, are to revolve freely on two rods, r 1", Which extend from one to another of two horizontal bars, s s, which go across the machine and are supported on the upper ends ofthe four guides m m m m.

A crank, t, fixed on one end of the shaft I, enables a person, by the proper application of manual power, to revolve the" screw k, and thereby move the plane-stock laterally, which he can do from time to time, as may be desirable.

The scrapers or reducing cutters, being borne down upon the work by the weight of the plane-stock, will reduce the said work on its upper surface while it may be in the act of being moved along.

The above-described machine will be found to be ofgreat utility in' scraping and polishing the tops of piano-fortes, as well as various `other plane surfaces, particularly those of veneered work.

I claim in the said machine as of my invention the followingthat is to say:

The combination ofthe movable shaft-boxes Z l, their guides m m m m, and lifting mechanism with the shaft I and its screw 7c, nut H, and the plane-stock G, applied to a movable carriage or bed to hold and move the work to be scraped or otherwise reduced, and to operate substantially as hereinbefore explained. Witnesses: FERDINAND HOFFMAN.

R. H. EDDY, F. l?. HALE, Jr. 

